Medical information display apparatus, medical information display method, and medical information display program

ABSTRACT

The medical information display apparatus includes an image acquisition unit that acquires a first brain image which is a brain image of a subject captured at a first time point and a second brain image captured at a second time point later in time than the first time point, a registration unit that performs registration between the first and the second brain image, an image analysis unit that extracts a first cavity region and a second cavity region from the first brain image and the second brain image, respectively, a display unit, and a display controller displays, a cavity expansion part included in a first non-cavity region, which is a region other than the first cavity region, and included in the second cavity region in a distinguishable manner from a region other than the cavity expansion part from a result of the registration between the first and second brain image.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of PCT International Application No.PCT/JP2018/021210 filed on Jun. 1, 2018, which claims priority under 35U.S.C § 119(a) to Patent Application No. 2017-164672 filed in Japan onAug. 29, 2017, all of which are hereby expressly incorporated byreference into the present application.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a medical information displayapparatus, a medical information display method, and a non-transitorycomputer readable recording medium storing a medical information displayprogram, and particularly relates to a medical information displayapparatus, a medical information display method, and a non-transitorycomputer readable recording medium storing a medical information displayprogram for supporting diagnosis of dementia for a subject (patient) bya doctor or the like.

2. Description of the Related Art

With the arrival of an aging society, the number of patients withdementia is increasing year by year. It is considered that dementiadevelops in a case where a protein called amyloid 3 accumulates in thebrain and accordingly brain atrophy progresses and cognitive abilitydeclines. At present, there is no effective treatment for dementia. Forthis reason, it is important in terms of maintaining the quality of lifeto detect brain atrophy early and start treatment early to delay theprogression of dementia.

In order to meet such a demand, in recent years, information regardingthe state of the brain can be acquired by nuclear medicine examinationssuch as single photon emission computed tomography (SPECT) and positronemission tomography (PET), CT images acquired by computerized tomography(CT) apparatuses, and MRI images acquired by magnetic resonance imaging(MRI) apparatuses. For example, decreased blood flow and metabolism in alocal part of the brain can be found by checking a temporal change inthe local part of the brain using SPECT and PET images.

On the other hand, brain atrophy can be found by calculating the volumeof a specific part of the brain using MRI images and comparing atemporal change in the volume. For example, in JP2014-042684A, a methodof performing registration of two brain images having different imagingdates and times, and then dividing each of the two brain images intotissue regions (gray matter and white matter) to acquire the changeamount for each tissue region has been proposed.

On the other hand, for example, a method of performing registrationbetween a standard brain image divided according to a Broadmann's brainmap and a brain image of a patient and dividing the brain image of thepatient into regions has been proposed (see JP2011-010828A). Here, theBroadmann's brain map shows that which region carries out certain brainfunction (movement, language, perception, memory, vision sense, acousticsense, and the like) within a three-dimensional region of the cerebralcortex of the standard brain. Thus, a method of dividing the brain imageof the patient into regions and acquiring the change amount in thevolume for each region has been proposed (Dominic Holland, et al.,Alzheimer's Disease Neuroimaging Initiative, “Subregionalneuroanatomical change as a biomarker for Alzheimer's disease”,Proceedings of the National Academy of Sciences, National Academy ofSciences, Dec. 8, 2009, vol. 106, no. 49, pp. 20954 to 20959 and YakangDai, et al., Alzheimer's Disease Neuroimaging Initiative, “aBEAT: AToolbox for Consistent Analysis of Longitudinal Adult Brain MRI”, PLoSONE, Public Library of Science, Apr. 3, 2013, vol. 8, issue 4). In themethod disclosed in Dominic Holland, et al., Alzheimer's DiseaseNeuroimaging Initiative, “Subregional neuroanatomical change as abiomarker for Alzheimer's disease”, Proceedings of the National Academyof Sciences, National Academy of Sciences, Dec. 8, 2009, vol. 106, no.49, pp. 20954 to 20959 and Yakang Dai, et al., Alzheimer's DiseaseNeuroimaging Initiative, “aBEAT: A Toolbox for Consistent Analysis ofLongitudinal Adult Brain MRI”, PLoS ONE, Public Library of Science, Apr.3, 2013, vol. 8, issue 4, first, a first brain image of the patient anda standard brain image are registrated to divide the first brain imageinto regions, and a second brain image of the patient whose imaging dateand time is later than that of the first brain image and a standardbrain image are registrated to divide the second brain image intoregions. Then, the change amount in the volume is acquired betweencorresponding regions in the first brain image and the second brainimage.

SUMMARY OF THE INVENTION

However, even though an analysis value such as an atrophy rate iscalculated as a numerical value for each region divided into a number ofregions, it is difficult for a doctor or the like to determine dementiabased on the numerical value for each region.

The present invention has been made in view of such circumstances, andit is an object of the present invention to provide a medicalinformation display apparatus, a medical information display method, anda medical information display program capable of appropriatelydisplaying an atrophy state of the brain in order to support a doctor'sdiagnosis of dementia.

A medical information display apparatus according to a first aspect ofthe present invention comprises: an image acquisition unit that acquiresa first brain image which is a brain image of a subject captured at afirst time point and a second brain image which is a brain image of thesubject captured at a second time point later in time than the firsttime point; a registration unit that performs registration between thefirst brain image and the second brain image; an image analysis unitthat extracts a first cavity region and a second cavity region from thefirst brain image and the second brain image, respectively; a displayunit; and a display controller that displays, on the display unit, acavity expansion part included in a first non-cavity region, which is aregion other than the first cavity region in the first brain image, andincluded in the second cavity region in the second brain image in adistinguishable manner from a region other than the cavity expansionpart from a result of the registration between the first brain image andthe second brain image.

According to the first aspect, in the medical information displayapparatus according to a second aspect of the present invention, thedisplay controller is configured to display, on the display unit, acavity contraction part included in the first cavity region in the firstbrain image and included in a second non-cavity region which is a regionother than the second cavity region in the second brain image in adistinguishable manner from a region other than the cavity contractionpart.

A medical information display apparatus according to a third aspect ofthe present invention comprises: an image acquisition unit that acquiresa first brain image which is a brain image of a subject captured at afirst time point and a second brain image which is a brain image of thesubject captured at a second time point later in time than the firsttime point; a registration unit that performs registration between thefirst brain image and the second brain image; an image analysis unitthat extracts a first cavity region and a second cavity region from thefirst brain image and the second brain image, respectively; a displayunit; and a display controller that displays, on the display unit, acavity contraction part included in the first cavity region in the firstbrain image and included in a second non-cavity region which is a regionother than the second cavity region in the second brain image in adistinguishable manner from a region other than the cavity contractionpart from a result of the registration between the first brain image andthe second brain image.

According to any one of the first to third aspects, in the medicalinformation display apparatus according to a fourth aspect of thepresent invention, the display controller is configured to display, onthe display unit, a cavity part that is a region commonly included inboth the first cavity region and the second cavity region in adistinguishable manner from a region other than the cavity part.

According to any one of the first to fourth aspects, in the medicalinformation display apparatus according to a fifth aspect of the presentinvention, the display controller is configured to display, on thedisplay unit, a non-cavity part that is a region commonly included inboth the first non-cavity region which is a region other than the firstcavity region in the first brain image and a second non-cavity regionwhich is a region other than the second cavity region in the secondbrain image in a distinguishable manner from a region other than thenon-cavity part.

According to any one of the first to fifth aspects, the medicalinformation display apparatus according to a sixth aspect of the presentinvention further comprises: a brain area division unit that divides atleast one of the first brain image or the second brain image into aplurality of brain areas, in which the image analysis unit is configuredto calculate a change of each brain area due to a change of the cavityregion in the first brain image and the second brain image, and thedisplay controller is configured to display the change of each brainarea on the display unit.

According to the sixth aspect, in the medical information displayapparatus according to a seventh aspect of the present invention, theimage analysis unit is configured to calculate at least one of a sizechange or a shape change of each brain area due to the change of thecavity region in the first brain image and the second brain image.

According to the sixth or seventh aspect, the medical informationdisplay apparatus according to an eighth aspect of the present inventionfurther comprises: a first data acquisition unit that acquiresinformation indicating correspondence between the brain area and a brainfunction, in which the display controller is configured to displayinformation on the brain function corresponding to each brain area onthe display unit.

According to any one of the sixth to eighth aspects, the medicalinformation display apparatus according to a ninth aspect of the presentinvention further comprises: a second data acquisition unit thatacquires a table showing relevance between at least one item included inclinical diagnostic information on dementia and the brain area, in whichthe display controller is configured to specify at least one itemincluded in the clinical diagnostic information corresponding to eachbrain area and display the specified item on the display unit based onthe table.

A medical information display method according to a tenth aspect of thepresent invention comprises: an image acquisition step of acquiring afirst brain image which is a brain image of a subject captured at afirst time point and a second brain image which is a brain image of thesubject captured at a second time point later in time than the firsttime point; a registration step of performing registration between thefirst brain image and the second brain image; an image analysis step ofextracting a first cavity region and a second cavity region from thefirst brain image and the second brain image, respectively; and adisplay control step of displaying, on the display unit, a cavityexpansion part included in a first non-cavity region, which is a regionother than the first cavity region in the first brain image, andincluded in the second cavity region in the second brain image in adistinguishable manner from a region other than the cavity expansionpart from a result of the registration between the first brain image andthe second brain image.

A medical information display method according to an eleventh aspect ofthe present invention comprises: an image acquisition step of acquiringa first brain image which is a brain image of a subject captured at afirst time point and a second brain image which is a brain image of thesubject captured at a second time point later in time than the firsttime point; a registration step of performing registration between thefirst brain image and the second brain image; an image analysis step ofextracting a first cavity region and a second cavity region from thefirst brain image and the second brain image, respectively; and adisplay control step of displaying, on a display unit, a cavitycontraction part included in the first cavity region in the first brainimage and included in a second non-cavity region which is a region otherthan the second cavity region in the second brain image in adistinguishable manner from a region other than the cavity contractionpart from a result of the registration between the first brain image andthe second brain image.

A medical information display program according to a twelfth aspect ofthe present invention for causing a computer to realize: an imageacquisition function of acquiring a first brain image which is a brainimage of a subject captured at a first time point and a second brainimage which is a brain image of the subject captured at a second timepoint later in time than the first time point; a registration functionof performing registration between the first brain image and the secondbrain image; an image analysis function of extracting a first cavityregion and a second cavity region from the first brain image and thesecond brain image, respectively; and a display control function ofdisplaying, on the display unit, a cavity expansion part included in afirst non-cavity region, which is a region other than the first cavityregion in the first brain image, and included in the second cavityregion in the second brain image in a distinguishable manner from aregion other than the cavity expansion part from a result of theregistration between the first brain image and the second brain image.

A medical information display program according to a thirteenth aspectof the present invention for causing a computer to realize: an imageacquisition function of acquiring a first brain image which is a brainimage of a subject captured at a first time point and a second brainimage which is a brain image of the subject captured at a second timepoint later in time than the first time point; a registration functionof performing registration between the first brain image and the secondbrain image; an image analysis function of extracting a first cavityregion and a second cavity region from the first brain image and thesecond brain image, respectively; and a display control function ofdisplaying, on a display unit, a cavity contraction part included in thefirst cavity region in the first brain image and included in a secondnon-cavity region which is a region other than the second cavity regionin the second brain image in a distinguishable manner from a regionother than the cavity contraction part from a result of the registrationbetween the first brain image and the second brain image. In addition,the medical information display apparatus according to another aspect ofthe present invention comprises: a memory for storing an instruction forcausing a computer to execute processing; and a processor configured toexecute the stored instruction, in which the processor acquires a firstbrain image which is a brain image of a subject captured at a first timepoint and a second brain image which is a brain image of the subjectcaptured at a second time point later in time than the first time point,performs registration between the first brain image and the second brainimage, extracts a first cavity region and a second cavity region fromthe first brain image and the second brain image, respectively, anddisplays, on the display unit, a cavity expansion part included in afirst non-cavity region, which is a region other than the first cavityregion in the first brain image, and included in the second cavityregion in the second brain image in a distinguishable manner from aregion other than the cavity expansion part from a result of theregistration between the first brain image and the second brain image.

According to the present invention, it is possible to support a doctor'sdiagnosis of dementia by displaying an atrophy state of the brain easilyand appropriately for the doctor.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a hardware configuration diagram showing the outline of asystem including a medical information display apparatus according tothe present invention.

FIG. 2 is a functional block diagram showing a function of a CPU of themedical information display apparatus shown in FIG. 1.

FIG. 3 is a diagram showing a standard brain image including divisioninformation.

FIG. 4 is a diagram showing a first brain image.

FIG. 5 is a diagram showing a first brain image divided into a pluralityof brain areas.

FIG. 6 is a diagram showing a table T3 including numbers indicatingbrain areas and names of the respective brain areas.

FIG. 7 is a diagram in which a brain image on the outer surface isnumbered to indicate brain areas.

FIG. 8 is a diagram in which a brain image on the inner surface isnumbered to indicate brain areas.

FIG. 9 is a diagram showing diagnostic data indicating ADAS testresults.

FIG. 10 is a diagram illustrating the association betweenthree-dimensional information of all voxels forming a brain image andbrain area labels.

FIG. 11 is a diagram showing the flow of a process of a brain areadivision unit and a process of an image analysis unit.

FIG. 12 is a diagram used to describe the creation of a first table.

FIG. 13 is a correlation diagram showing correlation between the scoreand the atrophy rate of a test item.

FIG. 14 is another correlation diagram showing correlation between thescore and the atrophy rate of a test item.

FIG. 15 is still another correlation diagram showing correlation betweenthe score and the atrophy rate of a test item.

FIG. 16 is a diagram schematically showing a first table.

FIG. 17 is a diagram showing an example of a medical image and medicalinformation displayed on a monitor.

FIG. 18 is a flowchart relating to display control of the medicalinformation in the medical information display apparatus.

FIG. 19 is a diagram showing examples of brain images at two timepoints.

FIG. 20 is a diagram showing a display example of a cavity regioncorresponding to the example of FIG. 19.

FIG. 21 is a diagram showing another display example of the cavityregion.

FIG. 22 is a diagram showing still another display example of the cavityregion.

FIG. 23 is a diagram showing another example of brain images at two timepoints.

FIG. 24 is a diagram showing a display example of a cavity regioncorresponding to the example of FIG. 23.

FIG. 25 is a diagram showing an example of an analysis result table.

FIG. 26 is a flowchart relating to a display of an analysis result.

FIG. 27 is a diagram showing an example (a three-dimensional display) ofa display of the brain image.

FIG. 28 is a diagram showing another example (a parallel display) of adisplay of the brain image.

FIG. 29 is a diagram showing highlighting of the brain area in anotherexample (a parallel display) of a display of the brain image.

FIG. 30 is a flowchart relating to display control in a paralleldisplay.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, embodiments of a medical information display apparatus, amedical information display method, and a medical information displayprogram according to the present invention will be described withreference to the accompanying diagrams.

<Apparatus Configuration>

FIG. 1 is a hardware configuration diagram showing the outline of asystem including a medical information display apparatus according tothe embodiment of the present invention.

The system shown in FIG. 1 is configured to include a medicalinformation display apparatus 1, picture archiving and communicationsystems (PACS) 2, an electronic medical record 3, and a magneticresonance imaging (MRI) apparatus 4.

The MRI apparatus 4 continuously measures nuclear magnetic resonancesignals from hydrogen, phosphorus, and the like in a subject andvisualizes the nuclear density distribution, relaxation timedistribution, and the like, and is an apparatus that acquires athree-dimensional image showing a part as a diagnostic target of apatient who is the subject. As an apparatus for acquiring athree-dimensional image of a subject, there is a CT apparatus capable ofacquiring a computed tomography (CT) image in addition to the MRIapparatus 4.

In the present invention, a diagnostic target part of a patient who is asubject is a brain, and the MRI apparatus 4 outputs an MRI image of thehead including the brain of the subject as a three-dimensional brainimage.

The three-dimensional brain image is configured as a set of axialtomographic images (slice images) according to a predetermined sliceinterval or slice thickness (for example, a group of several hundredimages). A voxel in each slice image corresponds to a pixel of atwo-dimensional image having a slice thickness, and each voxel hasthree-dimensional information.

The PACS 2 is a unit that centrally manages digital medical imageinformation, which is obtained from a plurality of examinationapparatuses (modalities), as electronic data. A three-dimensional brainimage captured by the MRI apparatus 4 that is one of the modalities isstored and managed by the PACS 2 and used for searching, browsing, andthe like by the electronic medical record 3 or the medical informationdisplay apparatus 1.

In the PACS 2, image storage and communication are performed using theimage format and communication protocol of digital imaging andcommunication in medicine (DICOM). In the image format of the DICOMstandard, parameters, diagnostic information, and the like at the timeof imaging can be stored in the header portion of the file. In thepresent embodiment, it is assumed that a plurality of three-dimensionalbrain images having different imaging dates and times for the samesubject are stored and managed in the PACS 2.

The medical information display apparatus 1 is obtained by installing aninformation output program according to the embodiment of the presentinvention on one computer 10, and the computer may be a workstation or apersonal computer that is directly operated by the doctor who performsdiagnosis or may be a server computer connected to these through anetwork.

The information output program is distributed in a state in which theinformation output program is recorded on an optical disc (recordingmedium), such as a digital versatile disc (DVD) or a compact disc readonly memory (CD-ROM), and is installed from the optical disc onto thecomputer 10 through an optical disc drive 18.

An operation unit 22, such as a mouse and a keyboard that function as anoperation unit, and a monitor (display unit) 24 are connected to thecomputer 10. Here, the monitor 24 of FIG. 1 may be a liquid crystalmonitor, or may be provided with a head mounted display instead of or inaddition to the liquid crystal monitor.

The computer 10 is configured to mainly include: a central processingunit (CPU) 12 that perform overall control of the operation of eachcomponent; a main memory 14 that stores an apparatus control program orserves as a working area at the time of executing the program; a storage16 such as a hard disk apparatus; the optical disc drive 18 for readingand writing various kinds of data and programs recorded on the opticaldisc; and a communication interface (communication I/F) 20 forexchanging necessary information with the PACS 2, the electronic medicalrecord 3, and the like.

In addition to various kinds of application software including a medicalinformation display program according to the embodiment of the presentinvention, a reference brain image, and various tables (will bedescribed later) used in the present invention, brain images of thesubject acquired from the PACS 2 through the communication I/F 20 andvarious kinds of information including diagnostic information acquiredfrom the electronic medical record 3 are stored in the storage 16. Thediagnostic information includes data indicating the test results ofalzheimers' disease assessment scale (ADAS) or alzheimer's diseaseassessment scale Japanese version (ADAS-Jcog).

FIG. 2 is a functional block diagram showing a function of a CPU 12 ofthe medical information display apparatus 1 shown in FIG. 1.

The CPU 12 functions as various processing units by executing themedical information display program stored in the storage 16. In thisembodiment, the CPU 12 has functions as an image acquisition unit 12A, adata acquisition unit 12B, a brain area division unit 12C, an imageanalysis unit 12D, an information processing unit 12E, and a displaycontroller 12F.

The image acquisition unit 12A acquires a three-dimensional standardbrain image Bs and a three-dimensional first brain image B1 and athree-dimensional second brain image B2 including the brain of the samesubject and having different imaging dates and times.

The standard brain image Bs is a three-dimensional brain image showing abrain having a standard shape and size and a standard density (pixelvalue), that is, a standard brain. The standard brain image Bs can begenerated by extracting brains from a plurality of brain images, whichare acquired by imaging the heads of a plurality of healthy persons witha three-dimensional image capturing apparatus, and averaging theplurality of extracted brains.

The standard brain image Bs includes division information for dividingthe entire brain into a plurality of brain areas. As a method ofdivision, for example, based on the Broadmann's brain map, within thethree-dimensional region of the cerebral cortex, it is possible to use amethod of dividing the cerebral cortex into brain areas responsible forfunctions, such as movement, language, perception, memory, vision sense,and acoustic sense. In addition, it is possible to use any known method,such as a method for division into six kinds of brain areas of cerebrum,diencephalon, mesencephalon, hindbrain, cerebellum, and medullaoblongata and a method of dividing the cerebrum into frontal lobe,parietal lobe, temporal lobe, and occipital lobe.

FIG. 3 is a diagram showing an example of the standard brain image Bsincluding division information, and the entire brain is divided into aplurality of brain areas. In this example, the standard brain image Bsis divided into a plurality of brain areas. For example, the standardbrain image Bs is divided into a plurality of brain areas according tothe Broadmann's brain map. In the brain area, a ventricle and a cavityother than the ventricle (a cavity filled with cerebrospinal fluid) maybe the brain area.

The image acquisition unit 12A can acquire the standard brain image Bsfrom the storage 16 or the PACS 2. In addition, the image acquisitionunit 12A can acquire a first brain image B1 (FIG. 4) and a second brainimage B2 (not shown) of the same subject having different imaging datesand times from the PACS 2 or the electronic medical record 3. In thisexample, the first brain image B1 has an imaging date and time earlierthan that of the second brain image B2, for example, an image six monthsor one year ago.

The data acquisition unit 12B acquires a table T3 shown in FIG. 6,diagnostic information (in this example, diagnostic data indicating atest result in ADAS) D1 shown in FIG. 9, and the like. The table T3 andthe diagnostic data D1 are used for display control of medical imagesand medical information in a case where the medical information displayapparatus 1 functions as a viewer.

In the table T3 shown in FIG. 6, numbers indicating brain areas(Broadmann field: 1 to 52) and descriptions of name and function of eachbrain area are stored so as to be associated with each other. Known datacan be used as the data of the table T3. The table T3 can be stored inthe storage 16 in advance, and can be read and used appropriately.

FIG. 7 is a diagram in which a brain image on the outer surface isnumbered to indicate brain areas, and FIG. 8 is a diagram in which abrain image on the inner surface is numbered to indicate brain areas.

The ADAS is one of various cognitive function evaluations. The ADAS isfor evaluating the cognitive function centered on memory in order totest dementia. As shown in FIG. 9, evaluation is performed based oneleven test items of word reproducibility, spoken language ability,auditory comprehension of language, difficulty in speaking inspontaneous speech, according to verbal command, finger and articledesignation, constructive action, idea movement, orientation, wordrecognition, and test teaching reproducibility and the ADAS score of 0to 70 points. The score is obtained by subtracting the number of correctanswers from the full score of each test item. In a case where allquestions are correct, the score is 0. In the example shown in FIG. 9,there are errors in 35 questions. For example, the test item 4“difficulty in speaking in spontaneous speech” is wrong in 4 of 5questions.

The data acquisition unit 12B can acquire diagnostic data D1 (FIG. 9)indicating the ADAS test result from, for example, the electronicmedical record 3 or the header portion of the image file complying withthe DICOM standard. The cognitive function evaluation is not limited toADAS and ADAS-Jcog, and mini mental state examination (MMSE), Wechsleradult intelligence scale-III (WAIS-III), revised Hasegawa type simpleintelligence evaluation scale, and the like can be used.

Returning to FIG. 2, the brain area division unit 12C is a unit thatdivides each of the three-dimensional first brain image B1 and thethree-dimensional second brain image B2 into a plurality of brain areas.

First, the brain area division unit 12C performs registration betweenthe standard brain image Bs shown in FIG. 3 and the first brain image B1shown in FIG. 4. The size and shape of the brain vary from person toperson. For example, in a case where the brain is compared with thestandard brain, the size and shape of the brain are different by about+15% at the maximum.

The standard brain image Bs and the first brain image B1 have differentsizes and shapes. Therefore, in order to divide the first brain image B1into a plurality of brain areas, the brain area division unit 12Cperforms first registration using landmarks common to the standard brainimage Bs and the first brain image B1.

As landmarks, specifically, feature points of characteristic regions,such as a number of cerebral sulci (upper frontal sulcus, inferiorfrontal sulcus, lateral sulcus, longitudinal cerebral fissure, and thelike) and ventricles (left and right lateral ventricles of the cerebralhemisphere, third ventricle, and fourth ventricle) included in thebrain, can be used. In this example, it is assumed that the standardbrain image Bs is registrated with the first brain image B1. This isbecause causing no deformation of the first brain image B1 can improvethe calculation accuracy of the analysis value (such as the atrophy rateof the brain area) by the image analysis unit 12D to be described later.

The brain area division unit 12C extracts landmarks from the standardbrain image Bs and the first brain image B1 for registration. Forexample, landmarks may be extracted by template matching using atemplate indicating a landmark, or may be extracted using adiscriminator that has been learned to discriminate landmarks includedin an image.

The brain area division unit 12C performs first registration so thatcorresponding landmarks (feature points) match each other between thestandard brain image Bs and the first brain image B1. In the presentembodiment, the first registration is registration by similaritytransformation. Specifically, the first registration is registration byparallel movement, rotation, and similar enlargement and reduction ofthe standard brain image Bs. The brain area division unit 12C performsthe first registration by performing similarity transformation of thestandard brain image Bs so that the correlation between the landmarkincluded in the standard brain image Bs and the corresponding landmarkincluded in the first brain image B1 is maximized.

After performing the first registration, the brain area division unit12C performs second registration for matching the standard brain imageBs with the first brain image B1 using the corresponding landmarks. Thesecond registration is registration by nonlinear transformation. As theregistration by nonlinear transformation, for example, there isregistration performed by nonlinearly transforming pixel positions usingfunctions, such as B spline and thin plate spline.

The brain area division unit 12C performs the second registration bynonlinearly transforming each pixel position of the standard brain imageBs after the first registration into a corresponding pixel positionincluded in the first brain image B1.

By applying three-dimensional information (division information afterregistration) of the boundary between brain areas divided in thestandard brain image Bs to the first brain image B1 after registratingthe standard brain image Bs with the first brain image B1 as describedabove, the brain area division unit 12C can divide the first brain imageB1 into a plurality of brain areas as shown by the broken lines in FIG.5.

The brain area division unit 12C divides the second brain image B2 intobrain areas. Specifically, third registration is performed usinglandmarks between the first brain image B1 and the second brain imageB2. In the third registration, image enlargement and reduction are notperformed, and parallel movement and rotation of the first brain imageB1 are performed to registrate the first brain image B1 with the secondbrain image B2. Alternatively, the second brain image B2 may beregistrated with the first brain image B1.

Since the first brain image B1 and the second brain image B2 are brainimages of the same subject having different imaging dates and times,both the brain images after the third registration have a very highdegree of matching. That is, the three-dimensional position of a certainpixel (voxel) in the three-dimensional first brain image B1 and a voxelof the second brain image B2 corresponding to the voxel are present atthe same three-dimensional position or the vicinity thereof.

Therefore, the brain area division unit 12C can match each voxel of thefirst brain image B1 and each voxel of the second brain image B2 witheach other by corresponding point matching based on local image featurescentered on the corresponding voxels, for example.

The brain area division unit 12C can divide the second brain image B2into a plurality of brain areas by performing matching between allvoxels of each voxel of the first brain image B1 and each voxel of thesecond brain image B2. That is, three-dimensional information of eachvoxel of the second brain image B2 acquired by acquiringthree-dimensional information of each voxel of the second brain image B2corresponding to each voxel (that is, a voxel based on the divisioninformation) of the boundary of the plurality of brain areas of thefirst brain image B1 is division information for dividing the secondbrain image B2 into a plurality of brain areas.

The method of dividing the first brain image B1 and the second brainimage B2 into a plurality of brain areas by the brain area division unit12C is not limited to the embodiment described above, and various knownmethods can be applied. For example, a method described inJP2011-010828A can be applied.

The brain area division unit 12C divides the first brain image B1 into aplurality of brain areas so that three-dimensional information(coordinates x, y, z) and brain area labels (numbers indicating brainareas) and/or names are associated with each other for all voxelsforming the three-dimensional first brain image B1 as shown in FIG. 10,and temporarily stores the results in the main memory 14 or stores theresults in the storage 16. Similarly, also for the second brain imageB2, three-dimensional information and brain area labels and the like areassociated with each other for all voxels, and the results are stored inthe main memory 14 or the storage 16. In addition, it is preferable tostore the correspondence between each voxel of the first brain image B1and each voxel of the second brain image B2. This is because a voxelmovement vector can be calculated based on the three-dimensionalinformation between corresponding voxels.

Each coordinate axis of the three-dimensional information (coordinatesx, y, z) of the brain image corresponds to each body axis (X axis:left-right, Y axis: back-abdomen, Z axis: head-tail). The origin (0, 0,0) can be set at a specific position outside or inside the brain, forexample.

The image analysis unit 12D is a unit that analyzes the first brainimage B1 and the second brain image B2 for each divided brain area andoutputs an analysis result (analysis value). For example, analysisresults, such as an atrophy rate, a volume change amount, a shape changeamount, a Z score, and a blood flow volume for each brain area, areoutput.

FIG. 11 is a diagram showing the flow of processing of the brain areadivision unit 12C and processing of the image analysis unit 12D.

In FIG. 11, the standard brain image Bs includes division informationfor dividing the entire brain into a plurality of brain areas. Bslindicates a plurality of brain areas (division information) of thestandard brain image Bs. By registrating the standard brain image Bswith the first brain image B1, division information indicating theplurality of brain areas of the standard brain image Bs after theregistration can be used as division information (B11) indicating theplurality of brain areas of the first brain image B1.

By applying the first brain image B1 having the division information ofthe plurality of brain areas to the second brain image B2 and performingassociation between the voxels, the second brain image B2 can besubstantially divided into the plurality of brain areas. B21 is adiagram showing a plurality of brain areas of the second brain image B2.B11 indicates a plurality of brain areas of the first brain image B1 inthe axial section, and B21 indicates a plurality of brain areas of thesecond brain image B2 in the sagittal section.

The image analysis unit 12D calculates the volumes of the plurality ofbrain areas of the first brain image B1 and the plurality of brain areasof the second brain image B2 for each same brain area. After calculatingthe volume, the atrophy rate of the brain is calculated as an analysisvalue for each brain area by subtracting the volume of the correspondingbrain area of the second brain image B2 from the volume of the brainarea of the first brain image B1 and dividing a value obtained as aresult of the subtraction by the volume of the corresponding brain areaof the first brain image B1.

The brain area atrophies in a case where the atrophy rate is a positivevalue, and expands in a case where the atrophy rate is a negative value.The volume of the brain area can be calculated by counting the number ofvoxels in the brain area (the volume per voxel is known).

In this example, the image analysis unit 12D calculates the atrophy rateas an analysis value for each of the plurality of brain areas. However,the volume change amount, the shape change amount, the Z score, and theblood flow volume for each brain area may be calculated as analysisvalues.

The volume change amount for each brain area can be calculated bysubtracting the volume of the corresponding brain area of the firstbrain image B1 from the volume of the brain area of the second brainimage B2.

The shape change amount can be calculated from the change amount of thesphericity of the corresponding brain areas of the first brain image B1and the second brain image B2, for example. The sphericity can bedetermined by the ratio of the surface area of a sphere having the samevolume as the brain area to the surface area of the brain area. Inaddition, the sphericity can be determined by calculating the absolutevalue of a change region between the brain area of the first brain imageB1 and the corresponding brain area of the second brain image B2.

The Z score can be calculated for each brain area of the first brainimage B1 and the second brain image B2 based on the following equation.

Z=(x _(ave) −x)/σ  [Equation 1]

Here, x: voxel value, x_(ave): average value of voxel values of healthypersons, σ: standard deviation of voxel values of healthy persons.

The image analysis unit 12D can calculate the blood flow volume for thefirst brain image B1 and the second brain image B2 by an arterial spinlabeling (ASL) brain perfusion examination for evaluating the blood flowdynamics of the brain without using a contrast medium.

The information processing unit 12E is a unit that calculates therelevance between a plurality of divided brain areas of the brain imageand a plurality of test items of the diagnostic test for dementia andcreates a table (first table T1 (FIG. 16)) that stores the relevancebetween a plurality of brain areas (in this example, brain areas of 1 to52) and a plurality of test items (in this example, test items of 1 to11). As shown in FIG. 12, an analysis value for each brain area of thebrain image of the patient (in this example, an atrophy rate of eachbrain area) and the test result of the diagnostic test for dementia (inthis example, the ADAS score) are collected, and the relevance betweenthe atrophy rate and the test items is calculated.

Specifically, in creating the first table T1, the information processingunit 12E acquires the atrophy rate of each brain area of brain images ofa number of patients and the score for each of the eleven test items ofthe ADAS from the image analysis unit 12D and the data acquisition unit12B.

FIGS. 13 to 15 are correlation diagrams showing the correlation betweenthe score of each test item and the atrophy rate.

The horizontal axis in the correlation diagrams shown in FIGS. 13 to 15indicates one test item of the eleven test items of ADAS, and thevertical axis in the correlation diagrams indicates the atrophy rate ofone brain area of a plurality of brain areas. In the ADAS, the number ofcorrect answers is subtracted from the full score of the test item toobtain a score. Therefore, the higher the score, the more incorrectanswers and the worse the evaluation of the cognitive function.

FIG. 13 shows a case where there is almost no correlation between thescore of the test item and the atrophy rate, FIG. 14 shows a positiveweak correlation, and FIG. 15 shows a positive strong correlation.

The information processing unit 12E calculates the relevance between theatrophy rate of each brain area of the brain image and the score foreach test item, and creates the first table T1 indicating the relevanceas shown in FIG. 16.

In FIG. 16, A_(i,j) (1≤i≤52, 1≤j≤11) indicates the relevance, and can bea correlation value of −1≤A_(i,j)≤1. In the brain area, atrophyprogresses over time. However, for example, in a case where theventricle and other cavities are divided as brain areas, the brain areaexpands. Therefore, in this case, a negative correlation value isobtained. In addition, FIG. 16 shows the relevance (A_(20,1)=0.45,A_(22,1)=0.30) between the test item (item 1) of ADAS and the brainareas (lower temporal gyms, upper temporal gyms) indicated by numbers 20and 22. However, these relevance values are not actually calculatedvalues.

The first table T1 created by the information processing unit 12E isstored in, for example, the storage 16, and is appropriately used asnecessary by the display controller 12F or the like. In addition, it ispreferable that the first table T1 is periodically updated by theinformation processing unit 12E. This is because a more reliable tablecan be obtained by creating the first table T1 using the analysis valuesand the diagnostic tests for each brain area of a larger number ofpatients. The first table T1 created by an apparatus or a system outsidethe medical information display apparatus 1 may be used. In this case,the information processing unit 12E is not necessary.

The display controller 12F generates a display image for displaying, forexample, a medical image (at least one brain image of the first brainimage B1 or the second brain image B2) or medical information (analysisvalue obtained by performing analysis for each brain area of the firstbrain image B1 and second brain image B2, the table T3, and thediagnostic data D1) on the monitor 24 and outputs the generated displayimage to the monitor 24, and has a function as an output unit.

FIG. 17 is a diagram showing an example of a medical image and medicalinformation displayed on the monitor 24.

In the example shown in FIG. 17, brain areas A10 and A11 having largeatrophy rates (brain areas where the atrophy rate exceeds a thresholdvalue) are displayed so as to be distinguishable from other brain areasas indicated by hatching. For example, by giving a red color to thebrain areas A10 and A11, the brain areas A10 and A11 can be displayed soas to be distinguishable from other brain areas by different colors. Inaddition, labels L10 and L11 can be given to the brain areas A10 andA11. As the labels L10 and L11, analysis values (in the example shown inFIG. 17, an atrophy rate expressed as a percentage) are given. Inaddition, numbers (Broadmann field: 1 to 52) indicating the brain areasA10 and A11, the name of the brain area, or the like may be displayed.

The display controller 12F can display necessary medical images andmedical information on the monitor 24 according to the operation of theoperation unit 22 by the doctor.

<Display Control of Brain Image>

Hereinafter, display control of the brain image in the medicalinformation display apparatus 1 will be described. In the presentembodiment, a doctor's diagnosis of dementia is supported by extractingand displaying a cavity region of the brain including the ventricle fromthe brain images of the patient at two time points.

FIG. 18 is a flowchart relating to display control of the medicalinformation in the medical information display apparatus 1.

As shown in FIG. 18, first, the data acquisition unit 12B receives andacquires an input of data of three-dimensional brain images of a patientat two time points (step S10). In the following description, in the dataof the three-dimensional brain images of the patient at two time points,the brain images of a patient captured at a first time point and asecond time point later in time than the first time point are referredto as a first brain image and a second brain image, respectively.

The data acquisition unit 12B can acquire an MRI image captured undervarious imaging conditions as a brain image. Types of the MRI imageinclude, for example, a T1 weighted image (T1WI), a T2 weighted image(T2WI), a fluid attenuated inversion recovery (FLAIR) image, aT2*weighted image (T2*WI), a diffusion weighted image (DWI), or thelike.

In the T1WI, a signal intensity of water is lower than that of thecerebral cortex, and the water is depicted in black. For this reason, inthe T1WI, the ventricle (a space in the brain where a cerebrospinalfluid is produced) is black. The T1WI has a feature that an anatomicalstructure such as the cerebral cortex (gray matter) and the white matteris easily grasped.

In the T2WI, a signal intensity of water is higher than that of thecerebral cortex, and the water is depicted in white. For this reason, inthe T2WI, the ventricle is white. The T2WI is useful for extractinglesions because many lesions are depicted with a high signal.

The FLAIR image is a T2 weighted image in which a signal of water issuppressed, and the ventricle is depicted in black, and the lesionadjacent to the ventricle is clearly depicted.

The T2*WI is an image in which a hemorrhagic lesion is depicted inblack, and is an image suitable for detecting a minute hemorrhagiclesion.

The DWI is an image obtained by imaging a diffusion motion (freemobility) of water molecules, and a signal intensity in a region wherethe diffusion of water molecules is decreased is relatively high and theregion is depicted in white. In acute cerebral infarction, the diffusionof water molecules decreases, which is useful for determining the regionof hyperacute cerebral infarction.

The medical information display apparatus 1 according to the presentembodiment receives a designated input for a diagnosis purpose from anoperator (a doctor or the like) by the operation unit 22. Theinformation processing unit 12E can specify the type of an MRI imagenecessary for the diagnosis according to the diagnosis purposedesignated by the operation unit 22, and acquire the specified type ofimage from the MRI apparatus 4. In the present embodiment, for example,the T1WI or T2WI image can be used to detect a change of the ventriclewhich is a cavity in the brain. In the following description, an exampleusing the T1WI in which the ventricle is depicted in black will bedescribed.

In the present embodiment, the type of image to be acquired by the dataacquisition unit 12B may be directly designated by the operation unit 22instead of the diagnosis purpose. In addition, in a case where thediagnosis purpose is designated, the types of images suitable for thediagnosis purpose are listed so that the data acquisition unit 12B canselect an image to be acquired from the list of the types of images. Thediagnosis purpose is designated before the image of the patient iscaptured, and it may be possible to provide an instruction of the kindof image to be captured to an operator (medical radiology technician orthe like) of the MRI apparatus 4 in accordance with designation of thediagnosis purpose.

Next, the image analysis unit 12D performs rigid registration betweenone of the first brain image and the second brain image and a standardbrain image showing a standard brain model based on a Broadmann's brainmap (step S12), and performs non-rigid registration therebetween (stepS14). In the following description, description will be made assumingthat the registration between the first brain image and the standardbrain image, but the registration between the second brain image and thestandard brain image may be performed. Here, the rigid registrationincludes, for example, a process of aligning respective centroidpositions and orientations without deforming an image to be registrated.The non-rigid registration includes a process of projecting a brain areaincluded in the standard brain image onto the brain image of the patientby deforming the standard brain image and aligning it with the firstbrain image.

Next, the brain area division unit 12C divides the three-dimensionalbrain image of the patient into a plurality of brain areas by usingresults of the registration in steps S12 and S14 (step S16). The brainarea division is performed based on results of a brain activation test,for example, statistical data showing a relationship between a functionof the brain and a blood flow volume obtained by measuring the bloodflow volume with a positron emission tomography (PET) scanner during theactivity of the brain.

Next, rigid registration (step S18) and non-rigid registration (stepS20) are performed between the first brain image and the second brainimage. Therefore, results of the brain area division of the first brainimage in step S16 can be reflected in the second brain image.

Next, the image analysis unit 12D performs image analysis and extracts acavity region from the first brain image and the second brain image(step S22), and the display controller 12F displays a brain imageincluding the cavity region on the monitor 24 (step S24).

In the T1WI, the cavity region is a region having a relatively lowsignal value, and is depicted in black, so that a region having abrightness equal to or lower than a predetermined threshold value can beextracted as the cavity region. On the other hand, in the T2WI, thecavity region is a region having a relatively high signal value, and isdepicted in white, so that a region having a brightness equal to orhigher than a predetermined threshold value can be extracted as thecavity region.

A method of extracting the cavity region is not limited to the abovemethod. For example, a non-cavity region of the brain may be extractedby a known technique, and a portion that has not been extracted may beset as a cavity region. Alternatively, a cavity region may be set indivision information of a standard brain Bs, the cavity region may beprojected in registration with the standard brain Bs, and the cavityregion may be obtained from the first and second brain images.

Then, a change of the cavity region in the first and second brainimages, that is, the cavity expansion and contraction can be determinedbased on check whether voxels detected from the first and second brainimages after registration are cavitied or non-cavitied, or registrationresults or contour changes.

In display of the brain image in the present embodiment, changes in sizeand shape of the cavity region can be easily visualized. In addition,based on the results of registration in steps S18 and S20, the imageanalysis unit 12D calculates the changes in size and shape for eachbrain area around the ventricle, so that the atrophy rate or expansionrate for each brain area is easily visualized.

In the present embodiment, the image analysis unit 12D may acquire ananalysis value for each brain area by image analysis of the brain area.As an analysis value, for example, a volume change amount, a shapechange amount, a Z score, a blood flow volume, and an evaluation valueof infarction or bleeding obtained by comparing at least one of a pastthree-dimensional brain image of the same patient or a three-dimensionalbrain image model of a healthy person with the three-dimensional brainimage of the patient, can be obtained. Among these, the evaluation valueof the infarction can be obtained, for example, as the amount of changein the size and shape of an infarct occurrence area detected as a whitearea in the DWI. In addition, the evaluation value of the bleeding canbe obtained, for example, as the amount of change in the size and shapeof a hemorrhagic lesion area detected as a black area in the T2*WI. Thetypes of analysis values in the present embodiment are not limited tothose listed above.

Brain area specifying information for specifying each brain area,function and position information, and an analysis value obtained byimage analysis of the image analysis unit 12D may be associated witheach other and stored in the main memory 14 as an analysis result table(analysis result table T10 of FIG. 25).

FIG. 19 is a diagram showing examples of brain images at two timepoints. (a) of FIG. 19 shows a brain image S10 at a first time point inthe past, and (b) of FIG. 19 shows a brain image S12 at a second timepoint later than the first time point, for example, the current orlatest time point.

In the example shown in FIG. 19, a ventricle H12 which is a cavityregion in the brain image S12 at the second time point is larger than aventricle H10 which is a cavity region in the brain image S10 at thefirst time point. That is, for a non-cavity region (for example, brainparenchyma) which is a part other than the cavity region, a secondnon-cavity region E12 at the second time point atrophies more than afirst non-cavity region E10 at the first time point.

FIG. 20 is a diagram showing a display example of a cavity regioncorresponding to the example of FIG. 19.

A brain image S30 shown in FIG. 20 is an image showing a differencebetween the brain image S12 at the second time point and the brain imageS10 at the first time point. In the brain image S30, an increase amountof the ventricle that is the cavity region is shown as a cavityexpansion part D30. A reference numeral E30 in the figure indicates anon-cavity part that is not the cavity region in both the first brainimage S10 and the second brain image S12, and a reference numeral H30indicates a cavity part that is the cavity region in both the firstbrain image S10 and the second brain image S12.

As indicated by a reference numeral E32 in FIG. 21, a color, abrightness, or a transparency of the non-cavity part may be changed anddisplayed in a distinguishable manner from other regions.

Further, as shown in FIG. 22, the atrophy rate for each brain area maybe displayed. In the example shown in FIG. 22, for the brain areasincluded in a cavity expansion part D30, brain area specifyinginformation including numbers and names indicating the brain areas, andfunctions and atrophy rates controlled by the brain areas are displayed.In the example shown in FIG. 22, the brain areas may be displayed indescending order of atrophy rate, for example. In addition, only thebrain area whose the atrophy rate is larger than a threshold value maybe displayed, or the brain area whose atrophy rate is up to the n-thorder from the highest priority may be displayed.

FIG. 23 is a diagram showing still another display example of the cavityregion. (a) of FIG. 23 shows a brain image S40 at a first time point inthe past, and (b) of FIG. 23 shows a brain image S50 at a second timepoint later than the first time point.

In the example shown in FIG. 23, a ventricle H50 which is a cavityregion in the brain image S50 at the second time point is smaller than aventricle H40 which is a cavity region in the brain image S40 at thefirst time point. That is, for a non-cavity region (for example, brainparenchyma) which is a part other than the cavity region, a secondnon-cavity region E50 at the second time point expands more than a firstnon-cavity region E40 at the first time point.

FIG. 24 is a diagram showing a display example of a cavity regioncorresponding to the example of FIG. 23.

A brain image S60 shown in FIG. 24 is an image showing a differencebetween the brain image S50 at the second time point and the brain imageS40 at the first time point. In the brain image S60, a decrease amountof the ventricle that is the cavity region is shown as a cavitycontraction part D60. A reference numeral E60 in the figure indicates anon-cavity part that is not the cavity region in both the first brainimage S40 and the second brain image S50, and a reference numeral H60indicates a cavity part that is the cavity region in both the firstbrain image S40 and the second brain image S50.

Also in FIG. 24, as in the example shown in FIG. 22, it is possible todisplay the atrophy rate and expansion rate for each brain area.

According to the present embodiment, the atrophy state of the brain inthe cavity region can be easily and appropriately displayed for thedoctor by displaying a change of the cavity region of the brain. In thismanner, it is possible to support a doctor's diagnosis of dementia.

In the present embodiment, the brain image showing a difference betweenthe brain image at the second time point and the brain image at thefirst time point is displayed, but the present embodiment is not limitedto this. For example, a three-dimensional image with transparent areasother than the cavity expansion part may be displayed.

The display controller 12F may display the test item corresponding tothe brain area whose size or shape is changed in accordance with thechange of the cavity region together with a table of FIG. 22 by usingthe first table T1 that stores the relevance between the plurality ofbrain areas and the plurality of test items shown in FIG. 16. Further,the display controller 12F may display analysis values other than theatrophy rate described below together with the table of FIG. 22.

In the present embodiment, it is also possible to display the analysisresults of the brain area stored in the analysis result table. FIG. 25is a diagram showing an example of an analysis result table.

In an analysis result table T10 shown in FIG. 25, numbers and names fordesignating brain areas are stored as brain area specifying information,and the brain area specifying information is stored in association witha function, a position, and an analysis value of each brain area.

FIG. 26 is a flowchart relating to a display of an analysis result.

As shown in FIG. 26, first, the display controller 12F acquires ananalysis value obtained by image analysis for each brain area (stepS30). Next, the display controller 12F assigns a color to the brain areaaccording to the analysis value (step S32), and causes the monitor 24 todisplay an image in which a color according to the analysis value isadded to the brain area (step S34).

The display controller 12F sets a brain area having the largest volumechange amount, volume decrease amount, or shape change amount to red,and designate a color of the brain area by a color scale thatsequentially changes to orange, yellow, yellow-green, green, blue, anddark blue as these values become smaller. The display controller 12Fsets a brain area having a relatively large evaluation value (size) ofinfarction or bleeding to red, and designate a color of the brain areaby a color scale that sequentially changes to orange, yellow,yellow-green, green, blue, and dark blue as these values become smaller.As a result, it is possible to highlight a brain area having a largeshape change or a brain area having a high evaluation value of a lesionand a relatively high importance in brain diagnosis.

In the present embodiment, a color according to an analysis value isadded to a brain area, but the present invention is not limited to this.For example, an analysis value may be displayed by changing a brightnessor a transparency of an image.

In addition, the type of analysis value to be displayed by a color orthe like may be switched by providing a menu for selecting the type ofanalysis value.

FIG. 27 is a diagram showing an example (a three-dimensional display) ofa display of the brain image.

The three-dimensional brain image B1 shown in FIG. 27 is a volumerendering (VR) image in which the brain is divided into brain areas anddisplayed three-dimensionally. In FIG. 27, the boundaries of the brainarea are indicated by broken lines. An operator can perform operationsof enlargement and reduction of a display, rotation, and orientationchange of the brain by the operation unit 22.

As shown in FIG. 27, in a case where a cursor is moved by the mouse ofthe operation unit 22 and a position in the three-dimensional brainimage B1 is designated (clicked), coordinates of the designated voxelare specified. The information processing unit 12E specifies the brainarea presenting at a position of the specified voxel, and acquires aposition and an extent thereof from the analysis result table T10. Then,the display controller 12F highlights the specified brain area byincreasing or maximizing a transmittance of a brain area other than thespecified brain area. The name, function, and analysis value of thespecified brain area may be acquired from the analysis result table T10and displayed on a pop-up display P10.

FIG. 28 is a diagram showing another example (a parallel display) of adisplay of the brain image.

In the example shown in FIG. 28, the three-dimensional brain image B1and an orthogonal three cross-sectional image S1 are displayed inparallel.

The three-dimensional brain image B1 may be displayed by changing acolor, a brightness, and a transparency of the brain area according tothe analysis value. In addition, in the three-dimensional brain imageB1, a color or a thickness of an outline of the brain area may bechanged according to the analysis value. In the three-dimensional brainimage B1, a display according to the analysis value and a display of anMRI image such as a T1WI may be switched.

In a display region of the orthogonal three cross-sectional image S1, azx cross-sectional image S1 zx, a yz cross-sectional image S1 yz, and anxy cross-sectional image S1 xy of the brain are displayed side by side.The zx cross-sectional image S1 zx, the yz cross-sectional image S1 yz,and the xy cross-sectional image S1 xy may be displayed by changing acolor, a brightness, and a transparency of the brain area according tothe analysis value. In addition, in the zx cross-sectional image S1 zx,the yz cross-sectional image S1 yz, and the xy cross-sectional image S1xy, a color or a thickness of an outline of the brain area may bechanged according to the analysis value. In the zx cross-sectional imageS1 zx, the yz cross-sectional image S1 yz, and the xy cross-sectionalimage S1 xy, a display according to the analysis value and a display ofan MRI image such as a T1WI may be switched.

An operator moves any of reference points Pzx, Pyz, and Pzy in the zxcross-sectional image S1 zx, the yz cross-sectional image S1 yz, and thexy cross-sectional image S1 xy by a mouse to move a reference point ofthe orthogonal three cross-sectional image, thereby displaying a desiredcross-section of the brain on the monitor 24. Cross lines Czx, Cyz, andCzy in the figure move in conjunction with the movements of Pzx, Pyz,and Pzy, respectively, and indicate a position of the cross-sectionalimage being displayed.

In the three-dimensional brain image B1 or the orthogonal threecross-sectional image S1, in a case where a position in thethree-dimensional brain image B1 or the orthogonal three cross-sectionalimage S1 is designated (clicked), coordinates of the designated voxelare specified. The information processing unit 12E specifies the brainarea presenting at a position of the specified voxel, and acquires aposition and an extent thereof from the analysis result table T10.Therefore, the display controller 12F increases or maximizes atransmittance of a brain area other than the brain area specified in thethree-dimensional brain image B1, and also decreases or minimizes abrightness of a brain area other than the brain area specified in theorthogonal three cross-sectional image S1 (making it the same color as abackground color or filling it in black), and thus highlights thespecified brain area.

In the example shown in FIG. 28, a menu M10 is displayed next to theorthogonal three cross-sectional image S1. The menu M10 includes a brainfunction button indicating a function of the brain. In a case where anoperator selects the brain function button from the menu M10 using theoperation unit 22, the display controller 12F highlights the brain areaA10 corresponding to the selected brain function button as shown in FIG.29. In the yz cross-sectional image S1 yz and the xy cross-sectionalimage S1 xy, the brain area A10 is displayed as the cross-sectionalimages A10 yz and AlOxy of the brain area, respectively. In the exampleshown in FIG. 29, only one brain area corresponding to the selectedfunction is shown, but in a case where there are a plurality of brainareas corresponding to the selected function, all the brain areas may behighlighted.

In the present embodiment, when a brain area is selected, another brainarea corresponding to the same function as the selected brain area maynot be displayed. In this case, after receiving an instruction of end ofdiagnosis and check of the selected brain area, an image of anotherbrain area corresponding to the same function as the selected brain areamay be displayed. In addition, in a case of displaying an image ofanother brain area corresponding to the same function as the selectedbrain area, the brain area may be selected and displayed according tothe relevance (correlation value) between the function and the brainarea.

The brain area may be selected and displayed according to the relevance(correlation value) between the function selected from the menu M10 andthe brain area. For example, only the brain area where the relevancebetween the function selected from the menu M10 and the brain area isthe maximum may be displayed, or the brain area whose relevance is equalto or higher than a threshold value or whose relevance ranking is up tothe n-th order from the highest priority may be selected and displayed.

In the menu M10, a color, a brightness, or a transparency of the brainfunction button may be changed according to the analysis value. Forexample, in a case where a part or the whole of the brain area relatedto a language function atrophies as compared with the past patientimage, a button related to the language function may be colored red.

In the present embodiment, the display controller 12F may createthree-dimensional data using the analysis value calculated for eachbrain area as a voxel value, and create the three-dimensional brainimage B1 using the three-dimensional data.

For each brain function, the display controller 12F may store theanalysis value as a voxel value for the voxel of the brain areacorresponding to the same function, and create three-dimensional data inwhich a voxel value other than the brain area corresponding to the samefunction is set to a predetermined value, for example, −9999. Therefore,the display controller 12F may perform color coding for each brain areaby a color scale according to the analysis value stored as a voxelvalue, and make the voxel having a voxel value of −9999 lighter incolor, lower in brightness, or transparent, for example. In this manner,the display controller 12F can create the three-dimensional brain imageB1 and the orthogonal three cross-sectional image S1 for selectivelydisplaying the brain area corresponding to each function. In this case,for example, it is possible to display the brain area corresponding toeach function such as “memory”, “language”, or “hearing”, reflecting theanalysis value.

In a case of selecting and displaying the brain area for each function,a brain area other than the brain area selected as an object to bedisplayed may not be displayed at all, or a certain area around thebrain area selected as an object to be displayed may be displayed. Inthis case, for example, in the three-dimensional brain image B1 and theorthogonal three cross-sectional image S1, display may be performed fora surrounding region having a maximum size of about 10% of the brainarea selected as an object to be displayed. In addition, the surroundingregion may be made lighter in color, lower in brightness, or transparentas the distance from the brain area selected as an object to bedisplayed increases. This makes it possible to check a situation aroundthe brain area selected as an object to be displayed.

In the three-dimensional brain image B1 or the orthogonal threecross-sectional image S1, a cursor is moved by the mouse of theoperation unit 22 and a brain area in the image is selected, and thusthe name, function, and analysis value of the brain area may bedisplayed on the pop-up display P10.

FIG. 30 is a flowchart relating to display control in a paralleldisplay.

In the example shown in FIG. 30, first, in the VR image B1 or theorthogonal three cross-sectional image S1, the information processingunit 12E determines whether or not a predetermined position isdesignated (clicked) by the mouse operation of the operation unit 22(step S50). In a case where a position designation input is detected(Yes in step S50), the information processing unit 12E specifiescoordinates on the monitor 24 at the designated position (step S52).Next, the information processing unit 12E specifies the brain areacorresponding to the coordinates of the designated position (step S54),and the display controller 12F displays the name, function, and analysisvalue of the brain area on the monitor 24 (step S56).

On the other hand, in a case where the operation unit 22 selects a brainfunction in the menu M10 related to a function (No in step S50 and Yesin step S58), the information processing unit 12E specifies the brainarea corresponding to the selected function (step S60), and the displaycontroller 12F displays the name, function and analysis value of thebrain area on the monitor 24 (step S62).

Display of the name, function, and analysis value of the brain area insteps S56 and S62 may be displayed in a pop-up for each brain area, ormay be displayed on a table together with the brain area specifyinginformation. In a case where the brain area specifying information orthe like is displayed in a table, the corresponding brain area may behighlighted in the three-dimensional brain image B1 and the orthogonalthree cross-sectional image S1 in a case of selecting the brain areaspecifying information of the table.

Then, in a case where the operation unit 22 inputs a display endinstruction (Yes in step S64), the display of the brain image is ended.

According to the present embodiment, information on another brain areahaving the same function as the brain area focused on as a diagnosistarget can be displayed on the monitor 24 at the same time. In thismanner, the analysis value of the brain area responsible for the samefunction can be checked at a glance. For example, since the atrophy rateof the brain area corresponding to the same function as the focusedbrain area can be displayed as an analysis value, diagnosis of dementiausing a brain image is facilitated.

The present embodiment is not limited to the medical information displayapparatus 1, and can be realized as a medical information display methodfor causing the medical information display apparatus 1 to perform eachstep of display control according to the present embodiment, a medicalinformation display program for causing a computer to execute eachfunction of display control according to the present embodiment, and anon-transitory recording medium that stores the medical informationdisplay program.

In the above present embodiment, for example, the hardware structures ofprocessing units for executing various kinds of processing, (such as theimage acquisition unit 12A, the data acquisition unit 12B, the brainarea division unit 12C, the image analysis unit 12D, the informationprocessing unit 12E, and the display controller 12F), are variousprocessors shown below. The various processors include a centralprocessing unit (CPU) that is a general-purpose processor that executessoftware (program) to function as various processing units, aprogrammable logic device (PLD) that is a processor whose circuitconfiguration can be changed after manufacture, such as a fieldprogrammable gate array (FPGA), and a dedicated electric circuit that isa processor having a circuit configuration that is designed forexclusive use in order to execute specific processing, such as anapplication specific integrated circuit (ASIC).

One processing unit may be configured by one of these variousprocessors, or may be configured by two or more processors of the sametype or different types (for example, a plurality of FPGAs or acombination of a CPU and an FPGA). Alternatively, a plurality ofprocessing units may be configured by one processor. As an example ofconfiguring a plurality of processing units using one processor, first,as represented by a computer, such as a client or a server, there is aform in which one processor is configured by a combination of one ormore CPUs and software and this processor functions as a plurality ofprocessing units. Second, as represented by a system on chip (SoC) orthe like, there is a form of using a processor that realizes thefunction of the entire system including a plurality of processing unitswith one integrated circuit (IC) chip. Thus, various processing unitsare configured by using one or more of the above-described variousprocessors as a hardware structure.

In addition, the hardware structure of these various processors is anelectrical circuit (circuitry) in the form of a combination of circuitelements, such as semiconductor elements.

EXPLANATION OF REFERENCES

-   -   1: medical information display apparatus    -   2: PACS    -   3: electronic medical record    -   4: MRI apparatus    -   10: computer    -   12: CPU    -   14: main memory    -   16: storage    -   18: optical disc drive    -   20: communication interface    -   22: operation unit (mouse and keyboard)    -   24: monitor    -   3012A: image acquisition unit    -   12A: image acquisition unit    -   12B: data acquisition unit    -   12C: brain area division unit    -   12D: image analysis unit    -   12E: information processing unit    -   12F: display controller    -   S10 to S24, S30 to S34, S50 to S64: each step of display control

What is claimed is:
 1. A medical information display apparatus,comprising: an image acquisition unit that acquires a first brain imagewhich is a brain image of a subject captured at a first time point and asecond brain image which is a brain image of the subject captured at asecond time point later in time than the first time point; aregistration unit that performs registration between the first brainimage and the second brain image; an image analysis unit that extracts afirst cavity region and a second cavity region from the first brainimage and the second brain image, respectively; a display unit; and adisplay controller that displays, on the display unit, a cavityexpansion part included in a first non-cavity region, which is a regionother than the first cavity region in the first brain image, andincluded in the second cavity region in the second brain image in adistinguishable manner from a region other than the cavity expansionpart from a result of the registration between the first brain image andthe second brain image.
 2. The medical information display apparatusaccording to claim 1, wherein the display controller displays, on thedisplay unit, a cavity contraction part included in the first cavityregion in the first brain image and included in a second non-cavityregion which is a region other than the second cavity region in thesecond brain image in a distinguishable manner from a region other thanthe cavity contraction part.
 3. A medical information display apparatus,comprising: an image acquisition unit that acquires a first brain imagewhich is a brain image of a subject captured at a first time point and asecond brain image which is a brain image of the subject captured at asecond time point later in time than the first time point; aregistration unit that performs registration between the first brainimage and the second brain image; an image analysis unit that extracts afirst cavity region and a second cavity region from the first brainimage and the second brain image, respectively; a display unit; and adisplay controller that displays, on the display unit, a cavitycontraction part included in the first cavity region in the first brainimage and included in a second non-cavity region which is a region otherthan the second cavity region in the second brain image in adistinguishable manner from a region other than the cavity contractionpart from a result of the registration between the first brain image andthe second brain image.
 4. The medical information display apparatusaccording to claim 1, wherein the display controller displays, on thedisplay unit, a cavity part that is a region commonly included in boththe first cavity region and the second cavity region in adistinguishable manner from a region other than the cavity part.
 5. Themedical information display apparatus according to claim 2, wherein thedisplay controller displays, on the display unit, a cavity part that isa region commonly included in both the first cavity region and thesecond cavity region in a distinguishable manner from a region otherthan the cavity part.
 6. The medical information display apparatusaccording to claim 1, wherein the display controller displays, on thedisplay unit, a non-cavity part that is a region commonly included inboth the first non-cavity region which is a region other than the firstcavity region in the first brain image and a second non-cavity regionwhich is a region other than the second cavity region in the secondbrain image in a distinguishable manner from a region other than thenon-cavity part.
 7. The medical information display apparatus accordingto claim 2, wherein the display controller displays, on the displayunit, a non-cavity part that is a region commonly included in both thefirst non-cavity region which is a region other than the first cavityregion in the first brain image and a second non-cavity region which isa region other than the second cavity region in the second brain imagein a distinguishable manner from a region other than the non-cavitypart.
 8. The medical information display apparatus according to claim 1,further comprising: a brain area division unit that divides at least oneof the first brain image or the second brain image into a plurality ofbrain areas, wherein the image analysis unit calculates a change of eachbrain area due to a change of the cavity region in the first brain imageand the second brain image, and the display controller displays thechange of each brain area on the display unit.
 9. The medicalinformation display apparatus according to claim 2, further comprising:a brain area division unit that divides at least one of the first brainimage or the second brain image into a plurality of brain areas, whereinthe image analysis unit calculates a change of each brain area due to achange of the cavity region in the first brain image and the secondbrain image, and the display controller displays the change of eachbrain area on the display unit.
 10. The medical information displayapparatus according to claim 8, wherein the image analysis unitcalculates at least one of a size change or a shape change of each brainarea due to the change of the cavity region in the first brain image andthe second brain image.
 11. The medical information display apparatusaccording to claim 9, wherein the image analysis unit calculates atleast one of a size change or a shape change of each brain area due tothe change of the cavity region in the first brain image and the secondbrain image.
 12. The medical information display apparatus according toclaim 8, further comprising: a first data acquisition unit that acquiresinformation indicating correspondence between the brain area and a brainfunction, wherein the display controller displays information on thebrain function corresponding to each brain area on the display unit. 13.The medical information display apparatus according to claim 8, furthercomprising: a first data acquisition unit that acquires informationindicating correspondence between the brain area and a brain function,wherein the display controller displays information on the brainfunction corresponding to each brain area on the display unit.
 14. Themedical information display apparatus according to claim 8, furthercomprising: a second data acquisition unit that acquires a table showingrelevance between at least one item included in clinical diagnosticinformation on dementia and the brain area, wherein the displaycontroller specifies at least one item included in the clinicaldiagnostic information corresponding to each brain area and displays thespecified item on the display unit based on the table.
 15. The medicalinformation display apparatus according to claim 10, further comprising:a second data acquisition unit that acquires a table showing relevancebetween at least one item included in clinical diagnostic information ondementia and the brain area, wherein the display controller specifies atleast one item included in the clinical diagnostic informationcorresponding to each brain area and displays the specified item on thedisplay unit based on the table.
 16. A medical information displaymethod, comprising: an image acquisition step of acquiring a first brainimage which is a brain image of a subject captured at a first time pointand a second brain image which is a brain image of the subject capturedat a second time point later in time than the first time point; aregistration step of performing registration between the first brainimage and the second brain image; an image analysis step of extracting afirst cavity region and a second cavity region from the first brainimage and the second brain image, respectively; and a display controlstep of displaying, on a display unit, a cavity expansion part includedin a first non-cavity region, which is a region other than the firstcavity region in the first brain image, and included in the secondcavity region in the second brain image in a distinguishable manner froma region other than the cavity expansion part from a result of theregistration between the first brain image and the second brain image.17. A medical information display method, comprising: an imageacquisition step of acquiring a first brain image which is a brain imageof a subject captured at a first time point and a second brain imagewhich is a brain image of the subject captured at a second time pointlater in time than the first time point; a registration step ofperforming registration between the first brain image and the secondbrain image; an image analysis step of extracting a first cavity regionand a second cavity region from the first brain image and the secondbrain image, respectively; and a display control step of displaying, ona display unit, a cavity contraction part included in the first cavityregion in the first brain image and included in a second non-cavityregion which is a region other than the second cavity region in thesecond brain image in a distinguishable manner from a region other thanthe cavity contraction part from a result of the registration betweenthe first brain image and the second brain image.
 18. A non-transitorycomputer readable recording medium storing a medical information displayprogram for causing a computer to realize: an image acquisition functionof acquiring a first brain image which is a brain image of a subjectcaptured at a first time point and a second brain image which is a brainimage of the subject captured at a second time point later in time thanthe first time point; a registration function of performing registrationbetween the first brain image and the second brain image; an imageanalysis function of extracting a first cavity region and a secondcavity region from the first brain image and the second brain image,respectively; and a display control function of displaying, on a displayunit, a cavity expansion part included in a first non-cavity region,which is a region other than the first cavity region in the first brainimage, and included in the second cavity region in the second brainimage in a distinguishable manner from a region other than the cavityexpansion part from a result of the registration between the first brainimage and the second brain image.
 19. A non-transitory computer readablerecording medium storing a medical information display program forcausing a computer to realize: an image acquisition function ofacquiring a first brain image which is a brain image of a subjectcaptured at a first time point and a second brain image which is a brainimage of the subject captured at a second time point later in time thanthe first time point; a registration function of performing registrationbetween the first brain image and the second brain image; an imageanalysis function of extracting a first cavity region and a secondcavity region from the first brain image and the second brain image,respectively; and a display control function of displaying, on a displayunit, a cavity contraction part included in the first cavity region inthe first brain image and included in a second non-cavity region whichis a region other than the second cavity region in the second brainimage in a distinguishable manner from a region other than the cavitycontraction part from a result of the registration between the firstbrain image and the second brain image.
 20. A medical informationdisplay apparatus according to another aspect of the present inventioncomprises: a memory for storing an instruction for causing a computer toexecute processing; and a processor configured to execute the storedinstruction, in which the processor acquires a first brain image whichis a brain image of a subject captured at a first time point and asecond brain image which is a brain image of the subject captured at asecond time point later in time than the first time point, performsregistration between the first brain image and the second brain image,extracts a first cavity region and a second cavity region from the firstbrain image and the second brain image, respectively, and displays, onthe display unit, a cavity expansion part included in a first non-cavityregion, which is a region other than the first cavity region in thefirst brain image, and included in the second cavity region in thesecond brain image in a distinguishable manner from a region other thanthe cavity expansion part from a result of the registration between thefirst brain image and the second brain image.